Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

If you have ever edited a locally checked out version of a file to tweak it for testing purposes, and came back to it over a weekend, you might have forgotten what you exactly changed. This command helps you see the differences between the the checked in SVN version, and the one you tweaked.

This will extract the differing CSS entries of two files. I've left the initial character (plus or space) in output to show the real differing line, remove the initial character to get a working CSS file. The output CSS file is usable by either adding it in a below the to original.css, or by only using the output but adding @import url("original.css"); in the beginning.

This is very useful for converting Wordpress theme copies into real Wordpress child themes.

Could exclude common lines within entries too, I guess, but that might not be worth the complexity.